Lecture 42- Respiratory System Part 2 Flashcards
What is Respiratory Distress Syndrome characterized by?
Difficulty breathing due to collapse of the alveoli
What do premature babies not have a significant amount of in their lungs?
Surfactant
What are the three layers in the blood-air barrier that gas exchange happens across?
- Alveolar cell layer
- Capillary Endothelial layer
- Fused basement membrane
How many lobes does the right lung have?
What are they called?
What are they separated b?
-Three lobes
-Superior, middle, and inferior
-Separated by an oblique fissure AND horizontal fissure
How many lobes does the left lung have?
What are they called?
What are they separated b?
-Two lobes
-Superior and inferior
-Separated by an oblique fissure ONLY
What is a pulmonary lobectomy?
Surgical removal of a cancerous/diseased segment of the lung, rather than the entire organ
Prevents spreading to other parts of organ
What covers the inner surface of the thoracic wall and extends over the diaphragm?
Outer layer
Parietal Pleura
What covers the outer surface of the lungs, extending into the fissures between the lobes?
Inner layer
Visceral Pleura
What are the two functions of Pleural fluid?
- Lubricates the pleural cavity (less friction)
- Creates a fluid bond which connects thoracic cavity and lungs to change in volume together
External respiration the exchange of oxygen between the body’s ______ ____ and the ____ ______
Interstitial fluids- fluid surrounding cells
External environments- space inside alveoli where air from the outside world enters in
What type of respiration is the absorption of oxygen and the release of carbon dioxide by cells called?
Internal Respiration
What is pulmonary ventilation?
Essentially breathing- physically moving air into and out of the lungs
What are the two locations that gas exchange occurs across the blood-air barrier?
- Lungs
- Tissues
Where does the transport of oxygen and carbon dioxide occur? (2)
- Between alveolar capillaries
- Between capillary beds in other tissues
What causes pulmonary ventilation?
Changes in thoracic cavity volume, which lead to pressure differences
Boyle’s Law states that when volume decreases, collision frequency and pressure will (decrease/increase/stay the same)
Increase
Boyle’s Law states that when volume increases, collision frequency and pressure will (decrease/increase/stay the same)
Decrease
What are the four factors that favor an increase in lung volume (inspiration)?
- Muscle contraction- lowers the floor of thoracic cavity/expands rib cage
- Negative intrapleural pressure- helps suction the lungs to thoracic wall
- Elastic recoil of the thoracic wall
- Surfactant in alveoli
What is the pressure from least to greatest when breathing in between the atmosphere, lungs, and intrapleural space?
PIP<PA<Patm
OR
Intrapleural space<Lungs/Alveoli<Atmosphere
What is the pressure from least to greatest when breathing out between the atmosphere, lungs, and intrapleural space?
PIP < PA > Patm
OR
Intrapleural space< Lungs/Alveoli> Atmosphere
If the pleural sac is punctured, what happens to the intrapleural pressure/volume? What will the lung do as a result?
Intrapleural pressure equalizes with atmospheric pressure.
Intrapleural volume increases
Lung collapses
What does compliance mean?
A measure of how easy it is to inflate the lungs
What does compliance of the lungs and alveoli depend on? (2)
- Negative intrapleural pressure
- Surfactant- disrupts hydrogen bonds in water layer to decrease surface tension
Would a smaller or larger alveoli will require a greater concentration of surfactant to maintain compliance?
Smaller
Smaller alveoli=greater pressure=needs more surfactant
What two factors favor a decrease in lung volume (expiration)?
- Elastic recoil of alveolar walls
- Muscle contraction for forced expiration/pushes abdominal contents up against the thoracic cavity
